few_shots: Example:
Problem/activity:
Find the general solution for:
$${\mathrm{cos}\left({\pi\over2}+x\right)=\mathrm{tan}{\pi\over4}}$$


Standard options: 
A. Prove the Pythagorean identity sin^(2)(θ) + cos^(2)(θ) = 1 and use it to find sin(θ), cos(θ),or tan(θ) given sin(θ), cos(θ), or tan(θ) and the quadrant of the angle.
B. Prove the addition and subtraction formulas for sine, cosine, and tangent and use them to solve problems.


Thought: An initial step when solving for x in this problem requires the use of the addition formula for cosine on the left side of the equation. Solving this problem does not require use of the Pythagorean identity.
Answer: B

Now, assign the following problem or activity to one or more relevant standards it aligns with.
shot_info: fl_problem_001894

HS
options: Apply properties of operations as strategies to add and subtract. (Students need not use formal terms for these properties.) Examples: If 8 + 3 = 11 is known, then 3 + 8 = 11 is also known. (Commutative property of addition.) To add 2 + 6 + 4, the second two numbers can be added to make a ten, so 2 + 6 + 4 = 2 + 10 = 12. (Associative property of addition.)

Understand subtraction as an unknown-addend problem. For example, subtract 10 – 8 by finding the number that makes 10 when added to 8.
problem_activity: Narrative
The purpose of this activity is for students to write a
\(10 + n\)
expression that is equal to a given expression. Each expression given has three addends, two of which make a ten.
Required Materials
Materials to Gather
Connecting cubes or two-color counters
Double 10-frames
Launch
Groups of 2
Give students access to double 10-frames and connecting cubes or two-color counters.
“Now you will write a
\(10 + n\)
expression with the same value as each of the given expressions.”
Activity
5 minutes: independent work time
3 minutes: partner discussion
Student Facing
Write a
\(10 + \boxed{\phantom{3}}\)
expression that has the same value as each expression.
\(5 + 7 + 5\)
\(3 + 7 + 6\)
\(1 + 9 + 9\)
\(4 + 8 + 6\)
\(8 + 10 + 2\)
If you have time, write as many expressions as you can with 3 numbers that are equal to
\(10 + 5\)
.
Student Response
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Activity Synthesis
Display each
\(10 + n\)
expression.
“In order to make adding three numbers easier, we can rewrite each expression as a
\(10 + \boxed{\phantom{3}}\)
expression.”
Invite students to say the value of each
\(10 + n\)
expression together.


correct_option_index: 0